News + Features

Why Do Dogs Eat Their Poop? Research Points To Wolf Ancestry

It might seem gross to us, but there’s a plausible theory now

By Justyne Yuen-Lee

It seems every dog parent’s nightmare is to see your pet chewing on an unknown something. You rush over and scream, “WHAT’S IN YOUR MOUTH?” and then it becomes a Samson and lion battle trying to open your dog’s mouth, only to find an old band aid, cotton pad, or something else equally random. But what really gets every dog parent grossed out is when you catch your dog snacking on poop! You search on Google and the results suggest that it might be because of stress or enzymes deficiencies, but these are all just guesses.

Even though eating poop isn’t technically harmful to dogs, some people are turned off so much that they want to give their pups away. It’s the poopy-breath and the following licking. Ugh. Yes, dogs will do gross things and no, that’s not a reason not to love them.

Our dogs seem to get themselves into everything – but why do they have to chew on everything?

Benjamin Hart, a vet and the director of the Center for Animal Behavior, and a team of researchers from the University of California surveyed almost 3000 dog owners about their dog’s poop eating or coprophagy habits. Research showed that there was no relation to age, dietary differences, or compulsive behaviors.

Results did yield the fact that 80% of poop-eating dogs preferred poop that was no more than two days old. So this led Hart and his team to theorize that this fresh poop habit goes back 15 000 years to wolves.

“Wolves typically defecate away from their dens, in part because feces contain intestinal parasite eggs. But if, say, a sick or lame wolf did its business at home, the waste wouldn’t necessarily be dangerous immediately. Parasite eggs usually don’t hatch into infectious larvae for a few days.

So how do you get rid of it? They [wolves] don’t have pooper-scoopers. If they eat it right away, it’s safe to eat. They won’t get infected by parasites.”

Modern day dogs still have this wolfish instinct even though most poop they find is parasite free. This theory, however, isn’t a conclusion, but a logical explanation.

James Serpell, a professor at the University of Pennsylvania, says this idea is “plausible.” He notes that the surveyed dog owners labelled their pups to be “greedy eaters” and he relates this fact to scavenging dogs.

Stray dogs have no choice but to forage for their every meal.

Scavenging dogs live off of scraps and sometimes this includes even human poop as well as the poop of other dogs and cats. Since pets are fed diets that are higher in fats and proteins, not all of these are digested and scavengers can eat the feces as a second hand food source.

Now that we’ve found out a possible reason why dogs eat poop, researchers are left to find a solution to stop our dogs from continuing to do so!